SRivers33

Hey everyone, first off, I have in fact read about Misfires but none were super applicable to my situation. I just wanted to whittle this down a little more. So here are the details and then my thoughts...


2002 WRX on E85 and a ECU tuned for WOT. 18PSI FP Turbo. Hallman Pro Manual Boost controller.

1.The car hasnt felt or sounded like its misfiring...Its only felt like a misfire today for about 15 seconds...then it smoothed out and was back to fine.

THE PROBLEM

2.So three days ago it threw a P0302 code for a misfiring no. 2 Cyl.
It is tuned for WOT and it had bogged down a bit when i shifted too low one day so i figured that was the reason and deleted the code.

3.Drove it 120+ miles without any issue and then last night it threw another code.....so i pulled the battery cable and replaced it 15 mins later to clear the code figuring it must be the same one. (My diag tool wasnt with me).

4.Today by the time i get to work the Check Engine light is on again. I check the code and find that now its throwing these codes...

P0301 Cyl 1 Misfire
P0302 Cyl 2 Misfire
P0303 Cyl 3 Misfire
P0304 Cyl 4 Misfire
P0546 EGR Tempsensor Circuit High



MY THOUGHTS

To address the Misfires first....

1. Ignition_______The previous owner and i are still friends...he thinks its an ignition problem...(My problem with that is 1.It would be strange for all the coil packs,spark plugs, plug wires, etc to all go out at once. No?)

2. MAF________If it was the MAF wouldnt it throw that specific code? Also i have a A/F gauge that reads anywhere from 15-17 during idle....this seems normal to me.

3. FUEL PRESSURE REGULATOR______This is an aftermarket version that has been on the car for over a year...

4. Vacuum Leak____Honestly no idea if this is it or not but one friend of mine says you would be able to hear it and....i cant hear anything different so....not sure

5. I have considered a compression test but dont see how i would lose enough in all 4 simultaneously to create this problem...

6. I have wondered if pulling the battery would have reset the ECU possibly and created more problems for myself since the tune that the timing is advanced for would no longer be there....??????


NOW FOR THE EGR CODE

Only thing i could think is its burned out.....i have a high flow cat.....





Is it possible that this was actually the first problem and it caused the misfires?




Any info would be greatly appreciated.